The conservative former president frequently dominates media coverage with a hardline on immigration and security, as he seeks to win voters from the far right National Front.

Some three-fourths of conservative and centrist voters have a favorable opinion of the more moderate Juppe while only 55 percent look favorably on Sarkozy, according to an Elabe poll for BFMTV published on Wednesday.

Given the ruling Socialists unpopularity, the winner of the Nov. 20 and 27 primary election has a good chance of making it to the run-off round of the presidential election in May, possibly against National Front leader Marine Le Pen.